A preliminary probabilistic seismic hazard assessment in terms of Arias intensity in southeastern Spain

Maps for a return period of 475 years, that is, for a 10% probability of exceedance in 50 years, and for different soil conditions, have been computed. The uncertainty in the final result is shown by depicting maps for the mean and mean+σ attenuation curves. Independently of the geological soil conditions, higher Arias intensity values have been obtained along the Betic Cordilleras. The most significant result is the value obtained in the Granada Basin, the most active and hazardous Spanish seismogenic area. It is of the order of 0.4 m/s for shallow soils, 0.3 m/s for deep soils, and 0.2 m/s for stiff rock conditions, for the return period quoted above. These are typical values for a moderate seismic hazard region.